Maybe explain the basic info =.=
It's best you always have the most recent version (probably 1.5.1 now)
You can't join any server without having the IP address. Ask someone with a server for the IP. It ain't easy to make your own server and your computer must be able to handle it aswell if you can.
To get rid of the Steve skin go to
www.planetminecraft.comTexture packs are actually quite easy to install. Close your Minecraft -> download the .rar file of the correct texture pack (some older texture packs might not work in the most recent version) -> put the .rar file in your texture packs folder -> start Minecraft and get ingame -> change texture packs
If you have any more questions, post nudes of your grandparents.